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rail transport l engineering
EQUIPMENT FOR THE RAILWAY INDUSTRY
ŽĎAS, a company based in Žďár nad Sázavou,
manufactures high-quality and reliable devices for
applications in the railway industry supported by cutting
edge technology and significant references. The company
mainly designs lines for the production of railway wheels
and axles, and presses designed for the assembly
and disassembly of railway wheelsets, always
to individual customer requirements.
ŽĎAS offers a complete line for forming
railway wheels, which consists of a heating rotary hearth furnace, four hydraulic
presses with unit drives, one rolling mill,
handling equipment, marking equipment,
and equipment for measuring the dimensions of the semi-finished wheels. Furthermore, the line is equipped with automatic
tool change in hydraulic presses, including the preheating of tools. At the beginning of the production process, the cut input material blank is placed into a rotary
hearth furnace. After heating, a manipulator places the material in the descaling device. When the scale has been removed,
the manipulator moves the heated block
to the CKZW 5600 upsetting press, where the block is centred into the press axis
by means of a centring device. In the
press, the block is compressed into the
shape of a disk and another manipulator
transfers it to the CKVZ 8000 forming
press, where the centring and forming
operation takes place. This is followed by
the operation of punching the formed semi-product in the CKVD 1000 punching
press. Then the final shape of the wheel is
rolled in a rolling mill. In the CKVP 4000
dishing press, the wheel plate is then sized
and dished. The finished wheel is marked
in the stamping press and its shape is measured to see if it corresponds to specifications. The company is also able to provide the equipment with remote
management, diagnostics, and data collection, which will provide input information for predictive maintenance and integration with Industry 4.0.
The axles are forged from vacuum steel
billets of the required quality. After being
heated to forming temperature, the basic
shape of the axle is forged on an integrated forging unit which consists of a CKNV
1000 push-down forging press, a QKK 1.5
forging manipulator, and a rotary lifting
table. The basic axle design is generally
forged using three die sizes, which allows
for forging within the required specifications of ±1.5 mm, with a high degree of for-
puter controlled heat treatment to achieve optimal mechanical properties. The deflection and shape deformation caused by
the heat treatment is then adjusted on an
RL 400 straightening press.
Railway bogie wheels must have different properties in different places of their
surface; they must be flexible and hard at
the same time. The required hardness
is achieved by reducing the elasticity, and
therefore only the area of the wheel that
rolls along the track is hardened. The
CDRA hydraulic press is used for assembling railway wheelsets and cold pressing.
The device also enables the pressing of
components between the wheels and the
pressing and inspection of the pressed joints. The press cylinder located in the fixed
crossbeam uses a selected force over the
pressed parts against the support crossbeam. The hydraulic wheel centring device
is located on this, and the hydraulic axle
centring device is located on the rear
crossbeam. The control system provides
press control and operation and fault diagnostics. The CDRM press is designed for
cold pressing and the pressing of railway
Railway bogie wheelsets assembled using the CDRA/CDRM hydraulic presses
ging action. High mechanical properties
of the axles are also achieved thanks to
forged depth in the diameter transitions.
After forging, the axle undergoes a com-
Axle straightening on the RL 400 hydraulic straightening press
wheelsets together. The device enables
the assembly and disassembly of wheelsets for locomotives and railway cars with
simultaneous recording of pressing force
characteristics depending on the length
of the pressed joint. After the pressing
is complete, a report for archiving the
complete process is printed. The press cylinder rests on a support beam which travels on wheels on two beams. Depending
on the type of wheelset, the pressing force is absorbed by a support beam in predetermined locked positions. The advantages of both devices include precise
control of the pressing force, simple operation, and high performance.
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special 2020
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